Sikora, J. J. (1968). Calling: A reappraisal of religious life. Herder and Herder.
Chicago-viite (17. p.)Sikora, Joseph John. Calling: A Reappraisal of Religious Life. [New York]: Herder and Herder, 1968.
MLA-viite (8. p.)Sikora, Joseph John. Calling: A Reappraisal of Religious Life. Herder and Herder, 1968.
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